US9532778B2 - Surgical filament snare assemblies - Google Patents

Abstract

A surgical filament snare assembly including an anchor capable of being fixated in bone and having a filament engagement feature. A first filament has a noose on a first portion of at least a first limb and has a second portion connected to the filament engagement feature of the anchor. Preferably, at least one free filament limb, which in some embodiments is a length of the first filament and in other embodiments is a second filament, is capable of being passed through tissue to be repaired and has at least one end passable through the noose to enable incremental tensioning of the tissue after the anchor is fixated in bone. The noose strangulates the free filament limb when tension is applied to at least one of the free filament limb and the noose.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to and is a divisional of U.S. patent application Ser. No. 12/977,154 filed Dec. 23, 2010, and entitled “SURGICAL FILAMENT SNARE ASSEMBLIES,” which is a non-provisional of U.S. Provisional Application No. 61/416,562 filed Nov. 23, 2010, and entitled “TISSUE ANCHOR WITH FRICTIONAL SUTURE ENGAGEMENT,” each of which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to filament assemblies for securing tissue to bone and more particularly to adjustable tensioning of tissue independent of anchor fixation.

Description of the Related Art

A common injury, especially among athletes, is the complete or partial detachment of tendons, ligaments or other soft tissues from bone. Tissue detachment may occur during a fall, by overexertion, or for a variety of other reasons. Surgical intervention is often needed, particularly when tissue is completely detached from its associated bone. Currently available devices for tissue attachment include screws, staples, suture anchors and tacks.

Arthroscopic knot tying is commonly practiced in shoulder rotator cuff and instability procedures. Typically, an anchor loaded with suture is attached to bone first. The suture is normally slidably attached to the anchor through an eyelet or around a post, such that a single length of suture has two free limbs. One limb of the suture is passed through soft tissue to be repaired such as a tendon or labrum. The two ends of the suture are then tied to each other, thereby capturing the soft tissue in a loop with the anchor. Upon tightening the loop, the soft tissue is approximated to the bone via the anchor.

Surgeons typically tie the suture ends by first placing a surgical sliding knot such as the Tennessee Slider or Duncan Knot. After tightening the loop, a number of additional half hitches or other knots are tied. The additional knots are needed because a conventional sliding knot does not provide the necessary protection against loosening or slippage, especially when tension is placed primarily on the limbs of the loop. Generally accepted practice is to follow the sliding knot with at least three reversed half hitches on alternating posts of the suture.

Before one or more half hitches or other knots can be added to the sliding knot, however, there exists a potential for the sliding knot to slip, that is, for the loop to enlarge as the tissue places tension on the loop. This has been referred to as “loop security” and can reportedly occur even in the hands of very experienced surgeons. Sometimes, even fully-tied knots may slip. Further, the overall size of a conventional knot can be obstructive or intrusive, especially in tight joints, which may damage cartilage or other tissue by abrasion with the knot.

Suture anchor systems with sliding and locking knots for repairing torn or damaged tissue include U.S. Pat. No. 6,767,037 by Wenstrom, Jr. Other suture anchor systems suited especially for meniscal repair are disclosed in U.S. Pat. No. 7,390,332 by Selvitelli et al. and are utilized in the OmniSpan™ meniscal repair system commercially available from DePuy Mitek Inc., 325 Paramount Drive, Raynham, Mass. 02767.

There are a number of suture implant systems which proclaim to be “knotless”, that is, to not require a surgeon to tie a knot during surgery. Many such systems control tension on tissue by the depth to which an anchor is driven into bone. U.S. Pat. Nos. 5,782,864 and 7,381,213 by Lizardi disclose certain types of suture anchors which capture a fixed-length loop of suture. Adjustable loop knotless anchor assemblies utilizing an anchor element inserted into a sleeve are described by Thal in U.S. Pat. Nos. 5,569,306 and 6,045,574 and in U.S. Patent Application Publication No. 2009/0138042. Other systems having clamps or other locking mechanisms include U.S. Pat. No. 5,702,397 by Goble et al. and U.S. Patent Application Publication No. 2008/0091237 by Schwartz et al.

It is therefore desirable to have robust yet adjustable fixation of tissue while minimizing both the number and size of knots to be tied by a surgeon, especially during arthroscopic repair procedures.

SUMMARY OF THE INVENTION

An object of the present invention is to meet or exceed the tissue tension control and holding power of currently available suture anchor assemblies for tissue repair procedures while reducing the number of half hitches or other knots to be tied by a surgeon.

Another object of the present invention is to reduce the size of the finished knot for the assembly.

A still further object is to simplify the overall knot tying process for the surgeon while providing enhanced loop security and knot security

Yet another object of the present invention is to provide incremental tensioning after anchor fixation.

This invention features a surgical filament snare assembly including an anchor capable of being fixated in bone and having a filament engagement feature. A first filament has a noose on a first portion of at least a first limb and has a second portion connected, including slidably or fixedly connected, to the filament engagement feature of the anchor. The noose, such as one or more half-hitches or a hangman-type noose, is capable of receiving at least one end of a free filament limb and strangulating it when tension is applied to at least one of the free filament limb and the noose.

In preferred embodiments, at least a first free filament limb, which in some embodiments is a length of the first filament and in other embodiments is a second filament, is capable of being passed through tissue to be repaired and has at least one end passable through the noose to enable incremental tensioning of the tissue after the anchor is fixated in bone. In some embodiments, the noose is retractable toward the anchor. At least one tube may be included to assist passing the free filament limb through the noose.

In certain embodiments wherein the noose is formed from at least one half hitch, the assembly includes at least two tubes capable of being removably inserted into different loops of the half hitch to provide passages for two ends of free filament limbs. In some embodiments, the tubes are joined together and have at least one handle for manipulating the tubes. Preferably, each tube is slotted to facilitate removal of the free filament limbs from the tubes.

This invention also features a surgical suture snare assembly having an anchor capable of being fixated in bone and having at least one passage and a suture engagement feature. A first suture has a noose on a first portion of at least a first limb and has a second portion passing through the passage and connected to the suture engagement feature of the anchor. A second suture has at least a first free suture limb which is capable of being passed through tissue to be repaired and has at least one end passable through the noose to enable incremental tensioning of the tissue after the anchor is fixated in bone, the noose strangulating the free suture limb when tension is applied to at least one of the free suture limb and the noose.

Yet another feature of this invention is a surgical suture snare assembly having an anchor capable of being fixated in bone and having at least one passage and a suture engagement feature. A first suture has a noose on a first portion of at least a first limb and has a second portion passing through the passage and connected to the suture engagement feature of the anchor. The first suture further has at least a first free suture limb which is capable of being passed through tissue to be repaired and has at least one end passable through the noose to enable incremental tensioning of the tissue after the anchor is fixated in bone, the noose strangulating the free suture limb when tension is applied to at least one of the free suture limb and the noose.

A still further feature of this invention is a method of surgically repairing tissue, including selecting an anchor capable of being fixated in bone and having a filament engagement feature. A first filament is selected having a noose on a first portion of at least a first limb and having a second portion connected, including slidably or fixedly connected, to the filament engagement feature of the anchor. The method further includes fixating the anchor in bone, selecting at least a first free filament limb, and passing it through the tissue to be repaired. At least one end of the free filament is passed through the noose, and the tissue is tensioned as desired after the anchor is fixated in bone, the noose strangulating the free filament limb when tension is applied to at least one of the free filament limb and the noose.

In some embodiments, the free filament limb is selected from a length of a second filament. In one embodiment, the second filament includes a second free filament limb which is also passed through the noose such that the tissue is captured between the first and second free filament limbs. In certain embodiments, tension is also applied to the noose by retracting it toward the anchor.

In other embodiments, the method further includes placing a stopper element on the free filament limb after it is passed through the noose to inhibit withdrawal of the free filament limb from the noose. In some embodiments, a knot is tied and slid toward the noose to serve as the stopper element. At least one tube may be removably inserted into the noose to assist passing the free filament end through the noose. In certain embodiments, the noose is formed from at least one half hitch having at least three openings. At least two tubes are removably inserted into different openings of the half hitch to provide passages for at least two ends of free filament limbs. At least two free filament ends are passed through different openings in the half hitch.

BRIEF DESCRIPTION OF THE DRAWINGS

In what follows, preferred embodiments of the invention are explained in more detail with reference to the drawings, in which:

FIG. 1 is a schematic side view of a surgical filament snare assembly according to the present invention having an anchor and a noose;

FIG. 1A is a schematic side view of a hangman-type noose andFIG. 1B is such a view of a half-hitch noose to be utilized according to the present invention;

FIG. 2 is a schematic side view of the assembly ofFIG. 1 removably connected with a cannulated driver for initially fixating the anchor with a threader loop passed through the noose;

FIGS. 3-10 are schematic side views illustrating a process for capturing and tensioning tissue to the surgical filament snare assembly according to the present invention, withFIG. 8A providing an example of a stopper knot shown inFIGS. 8, 9 and 10;

FIGS. 11 and 12 are perspective views of an alternative half-hitch noose in which multiple openings are utilized to strangulate two or more free filament limbs;

FIG. 13 is a perspective view of tubes to assist threading of free filament limbs through noose openings ofFIG. 11;

FIG. 14A is a perspective view of a double-barreled, slotted threader device;

FIG. 14B shows the device ofFIG. 14A being utilized to thread a noose;

FIGS. 15-19 illustrate different snare assemblies with retractable-noose configurations according to the present invention;

FIG. 20 is a schematic top view of multiple filaments that are passed through a single noose of a snare assembly according to the present invention;

FIG. 21 is an enlarged view of one construction of the configuration shown inFIG. 18;

FIGS. 22-27 are schematic side views of the snare assembly ofFIG. 18 utilized with another anchor placed through tissue to be repaired; and

FIG. 28 is a perspective view of a snare assembly according to the present invention having a cannulated suture anchor.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

This invention may be accomplished by a surgical filament snare assembly including an anchor capable of being fixated in bone and having a filament engagement feature. A first filament has a noose on a first, proximal portion of at least a first limb and has a second portion connected, including slidably or fixedly connected, to the filament engagement feature of the anchor. The noose, such as one or more half-hitches or a hangman-type noose, is capable of receiving at least one end of a free filament limb. The noose strangulates the free filament limb when tension is applied to the noose, to the free filament limb, or to both.

In preferred constructions, at least a first free filament limb, which in some constructions is a length of the first filament and in other constructions is a second filament, is passed through tissue to be repaired and has at least one end passable through the noose to enable incremental tensioning of the tissue after the anchor is fixated in bone.

Surgicalfilament snare assembly10,FIG. 1, has ananchor12 and afirst filament14. In this construction,anchor12 defines aninternal passage16 with a restrictedopening18 at itsdistal end20 which serves as a filament engagement feature. At least one bone-engagingfeature22, such as an external rib or helical thread, is located on the outer surface ofanchor12 betweendistal end20 andproximal end24.

First filament14 has anoose30 at its proximal end and a fixedknot32 at the distal end of filament post or stem15 which interacts with restrictedopening18 to retainfilament14 in a fixed, permanently attached position. This arrangement may be referred to as thefirst filament14 connected with thefilament engagement feature18, which includes the phrase passing through thefilament engagement feature18. Many conventional knots, such as a mulberry knot, can be utilized for fixedknot32 as long asknot32 has sufficient bulk to prevent pull-through at clinically desired tensions onnoose30. A number of other types of filament engagements are described below.Stem15 is kept as short as possible to maintainnoose30 close to anchor12 even after it is collapsed as described below.

A well-knownnoose knot33 is illustrated inFIG. 1A in which first filament14ahas a hangman-type noose30aat its proximal end and a fixedknot32aat the distal end ofstem15a.Noose30ahas slidingnoose knot33 and defines anopening34.Noose knot33 is tied by forming a flattened “S” or “Z” shape at the proximal end of filament14ato form a large proximal loop to serve as the noose opening and a small loop spaced from the large loop. The doubled filament limbs are wrapped with the terminal end, also known as the working end. After typically four to eight wrapping turns, the terminal end is tucked through the small loop and trapped by pulling on whichever of the limbs of the large loop closes the small loop.

An alternative, simpler noose is illustrated for first filament14b,FIG. 1B, having ahalf hitch35, also referred to as a simple or overhand knot, tied to formnoose30bin the middle offilament limbs36 and38. Multiple openings are created by the loops inhalf hitch35 as described in more detail below, althoughcentral opening37 is shown as a large single opening inFIG. 1B.First filament limbs36 and38 are folded aroundhalf hitch35 to form a double-stem arrangement, and the distal ends offirst filament limbs36 and38 are joined inknot32bafter being passed through a suitable filament engagement feature on an anchor.

Noose efficiency is defined herein as the strangulation strength per unit tension applied on the noose, either by pulling on the filament on which the noose is tied or which otherwise carries the noose, or by pulling on one or more strands or limbs of filaments passing through the noose. A noose with lower internal friction in the noose knot will tend to have a higher noose efficiency.

One instrument for insertinganchor12 into a hole drilled in bone is illustrated inFIG. 2.Driver40 has adistal end42 removably insertable intopassage16.Driver40 is cannulated in this construction and has alumen44 with anoptional threader filament46 that passes throughnoose30. Use of a threader filament is optional, but may be desirable whennoose30 is spaced only a short distance fromfilament engagement feature18, in other words, whennoose30 is initially positioned close to or inside ofanchor12.

In one procedure according to the present invention,anchor12 is shown fixated within bone B,FIG. 3, afterdriver40 has been removed, in ahole50 spaced at a desired distance from tissue T to be repaired.Noose30 is in an initial open configuration.Threader filament46 has a sufficient length to have both athreader loop52 on a first limb, and a graspable portion on asecond limb54, extend proximally above skin S while a mid-portion ofthreader filament46 is slidably associated withnoose30.

Continuing with this exemplary procedure, asecond filament60,FIG. 4, is threaded through tissue T using a suture passing instrument, a needle, or other tissue-penetrating technique chosen by a surgeon. Bothfree filament limbs62 and64 are brought together, typically above skin S, or at least outside of a joint space, and passed throughthreader loop52,FIG. 5.Threader limb54 is then pulled to thread bothsecond filament limbs62 and64 throughnoose30 as illustrated inFIG. 6 whilenoose30 is in the initial open configuration. Alternatively,free filament limbs62 and64 are passed directly throughnoose30 without using a threader filament.

When there is high noose efficiency, a light tug is sufficient to collapsenoose30 on thefilament limbs62 and64 as shown inFIG. 7 to provide initial tensioning on the surgicalfilament snare assembly10. Generally, a higher noose efficiency can be utilized when one or more free filament limbs are threaded directly throughnoose30 without using a threader filament, or are threaded using a tube or threader device such as shown inFIGS. 13-14B below.

After initial or pre-tensioning offree filament limbs62 and64,FIG. 7, tension is released onlimbs62,64 and aslidable stopper knot70,FIG. 8, is tied by the surgeon onlimbs62,64 above skin S. An enlarged view of one construction forstopper knot70a,FIG. 8A, shows a half hitch with an extra throw or turn, also known as a double overhand knot. A simple knot such as a single half hitch or overhand knot may be sufficient for some situations. Other suitable, more robust surgeon slidable knots with higher load capacity include the Tennessee Slider described in the Arthroscopic Knot Tying Manual (2005) available from DePuy Mitek, as well as the slidable, lockable knot by Wenstrom, Jr. in U.S. Pat. No. 6,767,037. Alternatively, a mechanical locking mechanism may be utilized where overall profile is not critical, especially away from a joint or other articulating surfaces.

Stopper knot70 is advanced, typically using a knot pusher, until itcontacts noose30,FIG. 9. Tension generated between tissue T andanchor12, alone or together with pulling on one of thefilament limbs62 or64, causesnoose30 to further collapse,FIG. 10, and strangulate the filaments.Stopper knot70 augments the strangulation by transferring all tissue-generated tension on the stopper knot to thenoose30 and preventing slippage offilament limbs62,64 into the noose knot. Accordingly, a self-cinching mechanism is created which inhibits loosening of the filaments. Tension can be increased incrementally in a ratchet-like effect by further advancing the stopper knot or pulling on one offilament limbs62,64.

Once satisfactory tissue tension has been achieved, one or more half hitches may be added tostopper knot70 to fortify the loading capacity on the stopper knot and reduce the risk of loosening under adverse conditions. By comparison, conventional sliding knots typically are reinforced by at least two or three reversed half hitches placed on alternating posts. Due to the self-cinching effect of the present invention, fewer overall hitches or other knots are needed forstopper knot70 to meet or exceed the load performance relative to conventional knot systems. The present invention thereby accomplishes a lower overall knot profile to handle a given load.Limbs62,64 are trimmed as desired. The stopper knot also minimizes fraying of the filament ends over time.

Preferred materials forfilaments14 and60 include various surgical sutures, typically size 0 to size 5, such as Orthocord™ suture commercially available from DePuy Mitek, and Ethibond™ suture available from Ethicon. Orthocord™ suture is approximately fifty-five to sixty-five percent PDS™ polydioxanone, which is bioabsorbable, and the remaining percent ultra high molecular weight polyethylene, while Ethibond™ suture is primarily high strength polyester. The amount and type of bioabsorbable material, if any, utilized in the first or second filament is primarily a matter of surgeon preference for the particular surgical procedure to be performed.

While the same type of suture, even identical suture, can be used for both first,noose filament14 and second,tissue filament60, a suture having a lower abrasive property at its surface may be preferred by some surgeons forsecond filament60. The lower abrasive property can be achieved by a larger diameter, a softer composition, a softer braid, plait or strand pattern, or a combination of such characteristics.

The nooses illustrated inFIGS. 1-6 above have been described as having a single opening through which one or more free filament limbs are threaded. A simple half hitch or overhand-type “pretzel”-like knot is illustrated inFIG. 11 fornoose30chaving multipleuseful openings80,82 and84.Side openings80 and84 are formed byminor loops81 and83 of the half hitch knot infirst filament limbs36c,38cwhilecentral opening82 is formed by the major loop.Free filament limbs62cand64care shown inFIG. 12 extending throughside opening80 andcentral opening82, respectively, although other combinations and permutations, such as usingside openings80 and84, orcentral opening82 andside opening84, are also effective. Utilizing different areas or regions of the noose knot significantly increases effective strangulation and gripping on the free filament limbs. It is expected that utilizing multiple openings in the noose knot also minimizes any dependence of load carrying capacity on filament compliance characteristics. A simple, single halfhitch stopper knot70cis also illustrated inFIG. 12.

While two or more threader filaments, or careful, potentially tedious manipulation by a surgeon, could be utilized to achieve the configuration shown inFIG. 12, an alternative technique which avoids inadvertent noose collapse is shown inFIG. 13.Tubes90 and92 have outer diameters suitable for sliding into the side openings formed byloops81 and83.Filament limbs36,38care shown engaged withanchor12c.Tubes90 and92 definepassages94 and96, respectively, through whichfree filament limbs62cand64care threaded.Tubes90 and92 are then disengaged fromnoose30cand drawn proximally alongfilament limbs62cand64cuntil they can be removed and discarded appropriately.

Double-barrelledthreader device100,FIG. 14A, has twothreader tubes102,104 which are joined together with ahandle106 and provide an even easier technique. In one construction,device100 is molded as a monolithic unit using a polymer material.Tubes102,104 haveinternal lumens108,110, respectively with openings at both ends as well asslots112,114, respectively, which also run the entire length oftubes102,104. During use,tubes102,104 are placed throughloops81d,83d,FIG. 14B, formed fromfirst filament limbs36d,38d, andfree filament limbs62d,64dare inserted throughlumens108,110. Thereafter,limbs62d,64dare simply lifted throughslots112,114 to remove the fully-threaded filaments from thedevice100. One or more additional such tubes can be formed and utilized as desired. Also, thetubes102,104 can be formed as “C” or “U” shapes in cross-section, with wider slots than illustrated.

There are a number of other configurations of snare assemblies according to the present invention which have one or more adjustable-length noose support stems or limbs that enable the noose to be retracted as desired toward an anchor. These configurations provide an additional level of control over the final filament positions and tensions.Snare assembly120,FIG. 15, has anoose124 formed at one end of afirst filament122 with astem section126 extending intoanchor130 to pass through ratchet-like one-way gate orclamping mechanism132. The remainder offilament122 serves as alimb128, also referred to as a stem tail. Some examples of one-way mechanisms are disclosed in U.S. Pat. No. 5,702,397 by Goble et al., for example, which allow filament movement in only one direction.

As illustrated inFIG. 15,anchor130 is fixated in bone B. Asecond filament134 is passed through tissue T and hasfree limbs136 and138 passed throughnoose124, initially positioned outside of a joint space surroundingtissue T. Limb128, also positioned outside of the joint space, is pulled to retractnoose124 towardmechanism132. Typically, thenoose124 is collapsed,limb128 is trimmed, and then a procedure similar to that illustrated forFIGS. 7-10 above is utilized.

Snare assembly140,FIG. 16, hasfirst filament140 having anoose144 tied with two stemlimbs146 and148 extending intoanchor150. In this construction,anchor post152 serves as a filament engagement feature to slidably attachfilament140 toanchor150. Filamentstem tail limbs154,156 extend out of a joint space, together withnoose144 in an initial configuration.Second filament160 is passed through tissue T and thenfree limbs162,164 are passed throughnoose144 outside of the joint space.

In the procedure illustrated inFIG. 16A,limbs154 and156 offirst filament142 are also passed throughnoose144 and then pulled to collapsenoose144 about all fourlimbs154,156,162 and164 and to retractnoose144 towardfilament engagement post152. One or more sliding knots are tied onlimb pair154,156 of the stem tails to adjust the proximity ofnoose144 to theanchor150 and then a simple knot is tied onfree limbs162,164 to adjust final tension on tissue T, although other combinations and permutations can be utilized within the scope of the present invention. Typically, the sliding knots are finished with one or more half hitches to “seal” or complete the fixation.

Snare assembly170,FIG. 17, utilizes asingle filament172 both to securenoose174 to anchor180 and to tension tissueT. Stem limbs176,178 pass intoanchor12 and slidably aroundfilament engagement post182 to emerge fromanchor180 astail limbs184,186 which are initially kept out of the joint space, along withnoose174, whenanchor180 is fixated in bone B. In some constructions,anchor post182 is an eyelet or a pulley pin.Free tail limbs184,186 are passed through tissue T, in the same or different places or regions, and then throughnoose174.Noose174 is collapsed and pulled into the joint space by applying light tension to one, or preferably both, of thetail limbs184,186. A simple stopper knot is tied betweentail limbs184,186 and pressed against thenoose174 while tensioning thelimbs184,186 to place a desired amount of tension on tissue T. The fixation is finalized by placing one or more half hitches against the stopper knot atnoose174.

Snare assembly190,FIG. 18, has functional similarities to snareassembly120,FIG. 15, but achieves ratchet-like noose retraction without one-way gate or clamping mechanisms.Filament192,FIG. 18, has anoose194 with astopper knot196 at its terminal end to prevent pull-through and to resist fraying. A slidingknot198 enablesloop200, havingloop limbs202 and204, to be shortened towardanchor205 whenpost limb206 is pulled.Loop200 passes around anchor saddle or post207. This and other adjustable loop, sliding knot configurations are described in more detail below in relation toFIGS. 21-27.

Snare assembly310,FIG. 19, includes afirst filament302 with anoose304 and aloop306 which is fixed in length, the overall length offilament302 being subject to full collapse ofnoose304. Asecond filament316 has aterminal end318, a slidingknot322 retained at the distal end ofanchor312, apost limb320, and anadjustable loop324 formed bylimbs326,328. This configuration is described in more detail below in relation toFIG. 28.

While most of the embodiments herein have been described in relation to securing one or two filament limbs passed through a single place or region in a tissue T, this is not a limitation of the invention.Snare assembly210,FIG. 20, has afirst filament211 with anoose212 through which passfree limbs214,216 and218,220 of second andthird filaments222 and224, respectively.Noose212 is engaged bystem213 withanchor215.Filaments222 and224 pass through tissue regions R1 and R2, respectively. Multiple regions of a tissue, and potentially multiple types of sutures or other filaments, can thereby be secured using a single snare assembly according to the present invention.

One arrangement of thefilament192 forsnare assembly190,FIG. 18, is illustrated inFIG. 21 forsnare assembly190a.Noose194ais formed merely by creatingopening232 inregion230 offilament192aand passingfilament192athrough itself.Loop200aand slidingknot198aare formed thereafter onpost limb206a. In this arrangement, any tension applied onstem234, such as by pullingpost limb206a, not only collapsesnoose194ato strangulate objects passing throughnoose194a, but also binds the portion offilament192apassing throughopening232 upon itself. In other arrangements, a half hitch or other simple knot is tied atfilament region230, andfilament192ais then looped through that simple knot.Stopper knot196asuch as a simple half hitch will prevent the terminal end from fraying or opening up, especially if a braided filament such as Orthocord™ suture is utilized forfilament192a.

An example of steps for manufacturingsnare assembly190,FIG. 18, utilizing suture asfilament192 is as follows.Tie stopper knot196 and trim the tail of the terminal end. Loop the suture and pass it through itself in close proximity to thestopper knot196 to achieve the noose arrangement illustrated inFIG. 21, or tie a second half hitch in close proximity to the stopper knot and pass the suture through the half hitch to create thenoose194,FIG. 18. A thin mandrel or other object such as a pin may be placed throughnoose194 to maintain patency. Slidingknot198, such as a bunt line half hitch knot, is tied in close proximity to thenoose194 and the suture is placed in sliding engagement withfeature207 ofanchor205. Slidingknot198 is then dressed or finalized as desired.

Conventionally, rotator cuff lateral row fixation involves spanning a suture bridge from medial anchors. Sutures are fixated with knotted or knotless anchors at the lateral row. Unthreaded anchors suffer more often than threaded anchors from anchor pull out, and suture slippage may occur at relatively low loads in many conventional procedures regardless of anchor type.

A presently preferred technique for rotator cuff double row repair is illustrated inFIGS. 22-27 utilizing the snare assembly ofFIG. 18.Medial row anchor240,FIG. 22, is shown already embedded in bone B having cuff tissue T fixated at the medial row withsuture242. Preferably, a threaded anchor is utilized foranchor240, and may be the same type of anchor asanchor205.Free suture limbs244 and246 are retracted out of the joint space, shown inFIG. 22 as extending beyond skin S. Threadedanchor205,FIG. 23 is then placed as a lateral row anchor in hole H independently of the medial row fixation. At this stage,collapsible loop200 is long enough to enable slidingknot198 andnoose loop194 to extend out of the joint space.

Suture limbs244,246 from the medial row are then passed throughnoose194,FIG. 24, preferably utilizing one of the threader devices described above. Any tension onsuture limbs244,246 will collapsenoose194 around them. The size of the threader tube may be selected to limit the migration ofnoose194 from slidingknot198.Post limb206 is then tensioned,FIG. 25, in the proximal direction indicated byarrow250 to retract slidingknot198 into or in close proximity to anchor205 and to place initial tension onsuture bridge258.

A simple knot such as a half hitch is then tied betweensuture limbs244,246 and pushed down againstnoose194,FIG. 26, as slidingknot260 whilelimbs244 and246 are pulled to furthertension suture bridge258 as desired. As second or morehalf hitches262,FIG. 27, are added aftersuture bridge258 has been properly tensioned to permanently lock the repair and the ends ofsuture limbs244 and246 are trimmed. Because a single noose can handle multiple pairs of sutures as described above in relation toFIG. 20, additional suture bridges can be secured from multiple medial anchors as desired.

Adjustablesuture snare assembly310,FIG. 28, has asuture anchor312 and a closed, fixed-length loop306 of afirst material302, which has anoose304 tied at one end. A half hitch “pretzel”-likeknot305 is shown in this construction.Loop306 is captured by, in other words, is connected to, asecond filament316 having aterminal end318, apost limb320, a sliding bunt linehalf hitch knot322, and anadjustable loop324 withloop limbs326 and328.Second filament316 may be considered as part of an adjustable filament engagement feature ofanchor12, becausefilament316 connectsnoose304 toanchor12. In one construction,suture anchor312 is similar to the cannulated suture anchor disclosed by Cauldwell et al. in U.S. Patent Application Publication No. 2008/0147063, incorporated herein by reference. In anchor systems utilized according to this sliding knot configuration of the present invention, however, it is not necessary to have a post-like suture-engaging member or other occluding element over which one or more sutures or suture limbs pass to serve as a restriction to proximal movement; in many constructions, it is sufficient to have a restrictedopening346 to prevent withdrawal ofknot322.

Suture anchor312 has aproximal end330 and adistal end332 with opposeddistal arms334 and336 defining cut-out338 between them.Passage340 is an inner lumen which runs fromproximal end330 to distal cut-out338. Althoughknot322 is shown extending beyond cut-out338 inFIG. 28 for purposes of illustration,knot322 preferably is seated against restrictedopening346 betweenarms334 and336, or otherwise maintained at thedistal end332 by a cavity or other feature, during insertion ofsnare assembly310 into a patient to minimize interference by theknot322 with the bone-engaging feature342, or other exterior surface ofanchor312, and the bone in whichsuture anchor312 is fixated.

One or more bone-engaging features342, such as the helical thread illustrated inFIG. 28 or other features such as teeth, ridges, or other protrusions, are formed on the exterior ofanchor312 to enhance fixation in bone. Threads such as found on the Healix™ anchor available from DePuy Mitek Inc. are desirable. In another construction, the suture anchor rotates to toggle into bone at its proximal end to minimize withdrawal. In a number of constructions, a hole is formed in bone prior to anchor insertion; in other constructions, a suture anchor is inserted directly into bone. Further, one or more passages or channels may be formed on the exterior of the suture anchor, such aschannel344 illustrated in phantom,FIG. 28, traversing bone-engaging element342.

It is a matter of surgeon preference whether aterminal end318 is kept at a length sufficient to lie against the exterior of at least one bone-engaging feature342 to be trapped against bone during insertion, or is trimmed to a shorter length. Further, a restriction such as restricted opening may be defined at least in part by engagement with bone whenanchor312 is fixated in bone to preventknot322 from moving withpost limb320 when tension is applied to postlimb320.

One or more such distal extensions or other protrusions may be provided, similar in some constructions to Cauldwell et al. cited above or to U.S. Pat. No. 7,381,213 by Lizardi, also incorporated herein by reference. In yet other constructions, a cylindrical or otherwise circumferential cavity, bowl or countersink feature is provided at the distal end of the anchor to seat theknot322 during insertion and fixation.

Slidable knot322 has been described as a bunt line half hitch knot in some constructions, but other suitable knots will be readily apparent to those of ordinary skill in the suture tying art after reviewing the present invention. The term “slidable” as used herein is intended to include slidable, lockable knots as well as slidable knots, such as those described in the Arthroscopic Knot Tying Manual (2005) available from DePuy Mitek, as well as the slidable, lockable knot by Wenstrom, Jr. in U.S. Pat. No. 6,767,037.

Thus, while there have been shown, described, and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions, substitutions, and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit and scope of the invention. For example, it is expressly intended that all combinations of those elements and/or steps that perform substantially the same function, in substantially the same way, to achieve the same results be within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale, but that they are merely conceptual in nature. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Every issued patent, pending patent application, publication, journal article, book or any other reference cited herein is each incorporated by reference in their entirety.

Claims (11)

What is claimed is:

1. A method of surgically repairing tissue, comprising:

selecting an anchor capable of being fixated in bone and having a filament engagement feature;

selecting a first filament having a noose on a first portion of at least a first limb and having a second portion connected to the filament engagement feature of the anchor;

fixating the anchor in bone;

selecting at least a first free filament limb and passing it through the tissue to be repaired;

passing at least one end of the first free filament limb through the noose; and

tensioning the tissue as desired after the anchor is fixated in bone, the noose strangulating the first free filament limb when tension is applied to at least one of the free filament limb and the noose,

wherein the noose is formed from at least one half hitch having at least three openings, and at least the first free filament limb and a second free filament limb are passed through different openings in the half hitch.

2. The method ofclaim 1 wherein the first free filament limb is selected from a length of a second filament.

3. The method ofclaim 2 wherein the second filament includes the second free filament limb which is also passed through the noose such that the tissue is captured between the first and second free filament limbs.

4. The method ofclaim 1 wherein the first free filament limb is selected from a length of the first filament.

5. The method ofclaim 4 wherein the first filament includes the second free filament limb which is also passed through the noose such that the tissue is captured between the first and second free filament limbs.

6. The method ofclaim 1 wherein tensioning the tissue includes retracting the noose toward the anchor.

7. The method ofclaim 1 further including placing a stopper element on the first and second free filament limbs after they are passed through the noose to inhibit withdrawal of the first and second free filament limbs from the noose.

8. The method ofclaim 7 wherein a knot is tied and slid toward the noose to serve as the stopper element.

9. The method ofclaim 1 wherein passing the at least one end of the first free filament includes removably inserting at least one tube into the noose, passing at least the one end of the first free filament limb through the tube, and then removing the tube from the noose.

10. The method ofclaim 1 further including removably inserting at least two tubes into different openings of the half hitch to provide passages for at least two ends of the first and second free filament limbs, passing at least one end of one of the first and second free filament limbs through one of the tubes and passing at least one end of another of the first and second free filament limbs through the other tube, and then removing the tubes from the noose.

11. The method ofclaim 10 wherein the tubes are joined together, and each tube is slotted to facilitate removal of the first and second free filament limbs from the tubes.

Images